Researchers studied 169 newlywed heterosexual couples over the first year and a half of their marriage, checking in with them every six months. At each check-in, husbands and wives self-assessed their levels of the 'Big Five' personality traits:

1. Openness - This refers to your levels of curiosity and desire for adventure. Those who score high for openness enjoy novelty and are generally creative. Those who score low in this trait think more conventionally, preferring their routines.

2. Extroversion - Essentially, this means your levels of cheerfulness, initiative and communicativeness. Those with high levels of extroversion are companionable, sociable, and able to accomplish self-determined tasks, while those with low levels are more introverted, reserved, and submissive to authority.

3. Conscientiousness - This trait reflects how organized you are. Those who score high for conscientiousness tend to be motivated, disciplined, and trustworthy, while those who score low are more irresponsible and easily distracted.

4. Agreeableness - Perhaps unsurprisingly, scoring high in this personality trait means you're naturally friendly, empathetic, and warm. Those who score low in agreeableness, however, tend to be shy, suspicious, and egocentric.

5. Neuroticism - This scale gauges a person's emotional stability. Those who score high in neuroticism are more anxious, inhibited, and temperamental, while those at the lower end of the spectrum are more calm and confident.

Overall, the study showed that newylwed couples' personalities changed 'for better' and 'for worse'during the first year. While husbands grew more conscientious as they adjusted to married life, they also became less extroverted. Though wives became less anxious, depressed, and angry after tying the knot, they also became less open to new experiences.

Interestingly, the research showed that both husbands and wives became less agreeable over the 18-month period, which may explain why that first year is just so hard. "Taken together, these findings indicate that newlywed spouses' personalities undergo meaningful changes during the newlywed years and these changes are associated with changes in spouses' marital satisfaction," the study concluded.

The results applied equally to the spouses studied, regardless of age, demographics, living arrangements, initial marital satisfaction, parenthood status, or even the length of the relationship. "The patterns of change we observed suggests there's something about the transition to marriage itself rather than other factors, such as getting older or being with your partner for longer," Justin Lavner, lead researcher and assistant professor of psychology at the University of Georgia, told Huffington Post. "The newlywed period may be marked by even more changes than we had previously thought."

While these findings may help newlyweds take their spouse's changing behavior with a grain of salt, the study acknowledged that further research is needed to understand the processes behind these personality changes early in marriage and to examine the mechanisms that may link changes in personality with changes in marital satisfaction.

So if you and your spouse experience more personalities clashes during your first year of marriage, that doesn't mean you should call it quits. Give each other some time to adjust to married life because change is hard, but marriage doesn't have to be.